Fiber cleaner



y 7, 1957 E R. w. POLLEYS 2,791,158

FIBER CLEANER Filed April 6, 1954 2 Sheets-Sheet 1 Q j a" 52 Envcntor attorney R- W. POLLEYS FIBER CLEANER May 7, 1957 2 Sheets-Sheet 2 Filed April 6. 1954 '2,"1 'i,'iss

FIBER CLEANER Richard w. i eiie s, wet Chester, 1 5., ,as'signar re Downing'tofwn Manuraetunn co npany, Ddv'vning'town, Pa., a eurparanan of Pennsylvania Application April 6,1954; Serial'No."421;2 23" stilai'ms'. (Ci. 92- -"2s This invention relates to a ihetlro'd'and apparatus for cleaning materials such "as parser stock used in paper making, and is particularly useful for efficiently and economically sepaiati'ng and reinoving sand and'othe'r foreign particles from paper making fibers such as employed in the manufacture of paper and fiber board.

The apparatus is adapted to effectively handle the stock directly as it comes from the usual fibe'r pnlper at a consisteficy of tram about 2.5% to about 4% without special treatment, such as thinning the stock, 'befor'e b'eih'g introduced into the apparatus.

The primary "object of the i'nv'eiitibh is the provision of high capacity stock cleaning apparatus er simple and rugged eera'iraaibn adapted to effectively clean the fiber stock with low power r'e'q'u'i're'r'rieizits.

Another object of the inveh on is the provision of a fiber stock creamer adapted to street thorough separation of'dirt particles or other detritus'from the "stock witho'u't employin pressure introduction "of the ist'o'ck.

Another object ofthe inve'rit'ion is the provision of a centrifugal separator in which there are no dead spots or areas of Zero centrifugal force, thus ensuring elfe'ct'ive rejection of all dirt particles in the separator.

A further object of the invention is the provision 'of 'a centrifugal separator having a plurality of serial outlets through which rejected dirt particles thrown out of the stock stream as it flows through the separator pass for discharge, and into which rejected particles cannotretui'ii into thesto'ck stream.

Another object of the invention is 'the provision'of 'a stock cleaner employing serially arranged rotating trundated hollow cones arranged to provide a central flow passage for the stock and a plurality of .peripheral outlets for the discha rgeof centrifugally thrown dirt particles.

Another object has to do with an arrangement of control valves in association with a collecting hopper for the rejected dirt particles phereby periodic removal of the collected particles may be effected without interrupting service of the apparatus.

How the foregoing, together with such other objects and advantagesas 'may'hereinafter appear or are incident to-the invention are-realized, is-illustrated 'in the accompanying drawings, wherein Fig. 1 is an elevational view of apparatus constructed in'accordance with the invention;

Fig. 2 is an enlarged fragmentary elevational view of automatic valve mechanism employed-in the apparatus;

Fig. is a fragrnen'ta'ry vertical section through the separating portion of the apparatus, the section at "the upper or stock inlet portion being taken on the line 3-- 3 of Fig. 4 and the remaining portion being taken on the line -33 of Fig. 5;

Fig. 4 is a-plansection on the line 4-4 of Fig.3; and

Fig. 5 is a plan section on the line 55 of Fig. 3.

The apparatus comprises in general a vertically mounted separator section A, an inlet elbow structure-B,-a

bearing and motor support C, a driving motor D, an

tes Patent C) 2,79 1,158 lZ-atentecl May 7, 1957 2 outlet elbow stru'cture E, a collecting hopper E, a hopper inlet valve G and a hopper dischargegate H;

The separator section A is composed of a cylindrical casing 7 having a top flange 8 to which the inlet elbow structure'B is secured anda bottomflange' 9 to which the outlet elbow structure E is secured. Suitable legs v10 are provided on the casing 7 for supporting the apparatus in a vertical position.

A central vertical shaft 11 drivingly connected to the motor shaft extends through thecasing A and is 'rotatively supported at its upper end in a bearing .12 mounted in the motor "support G-andat its'lowerendin a bearing-13 carried by the outlet elbow structure, E. Suitable-packingdevices 1-4 and-l5 are provided for'the shaft 11:.

Within the casing 7 the shaft 11 carries a plurality of hollow truncated separator or impeller cones 1'6, :17, 1'8 and 19 having vanes 20-, 29, these vanes being connected between the cones and :the hubs The h'ub of the lower cone 19 rests on a positioning'collar 22 welded on the shaft and the hubs of the remaining cones r'est'one onthe other. Set screws 23 are provided to secure the impeller cones on the shaft for rotation therewith.

The taper'of the cone impellers is such that annular outlets 24 are provided between successive impellers for the discharge of dirt particles from the oentr'alfiber stock stream into the annular chamber 25 surrounding the impeller-cones.

The inlet elbow structure B includes an inwardly direc-ted offset inlet portion 26 --('see Fig. 4) havinga :fiang: 27 to which an inlet pipe is secured. This iiiletspipe is connectedat its otherendto a fiberZpul-per orto ahead box of any well known type and leads the isto'ck' directly therefrom into the separator. The -:otfset inlet portion -216 provides for tangential introduction of the stock. The

portion 33 in concentric spacetlrelation to the sha'ftrli.

The outer diameter of the ring :portion 33 is of suchirelation to the top or smaller diameter-of the-top 'cone-i-rnpeller 16 as to .provideah annular running clearan'cefi t therebetween. This clearanceis of somewhat exaggerated size as shown in the drawings. The portion :33 extends somewhat downwardly into the top portion-of the cone 16 as clearly shown inFigure 3.

The outlet elbow structure E includes an outwardly directedoutlet portion 35 having 'a flange 36'to which an outlet or delivery pipe 37 is secured. This outlet pipe 37 delivers the cleaned stock to a 'point of use "o'r'to storage for future use.-

The outletpo'rtion 35 is of elbow form and terminates at its upper end in a circular ring .portion38-i'n concentric spaced relation to the shaft 11 and extending 'upwa'rdly somewhat into the lower portion of the lowermost cone impeller in spaced concentric relationtherewith as shown The structure E also includes a venturi shaped portion 40 ofiset to-one side of the shaft 1' 1 and opening at-the top into an annular chamber 41 in surrounding'relation to the upper part of the e1bow35. This "chamber *41 is in communication with the annular chamber 25 -to7receive rejected dirt particles therefrom. Theulower end of theventuri portion 40 terminates :in a ci'rcularopehing 42 having a surrounding flange -43. :Suitablewall structure 44- is provided around the "elbow '35 to merge the annular chamber 41 with the venturi '40.

The elbow "structure E -is alsoz-provided with ?:a top fian'ge 45 for "securing it to the casing flange fl as by means of bolts 46.

In operation the cone impellers are rotated at high speed, say by way of illustration from about 800 R. P. M. to about 900 R. P. M., and the stock enters at the top through the tangential inlet 26 into the volute casing 31 and then is directed downwardly in swirling motion into the interior of the rotating cone impellers where dirt particles, even minute sand specks, are thrown centrifugally outwardly and downwardly through the plurality of annular outlets 24 and into the annular chamber 25 material passes through the annular outlets to the outer annular settling chamber, the arrangement being such that the rejected material once it has left the interior of the cones cannot return and re-enter the flowing stream of cleaned stock. The apparatus operates to remove all particles having specific gravities higher than that of the cellulose fiber and water mixture.

It will be seen that all particles arepositively rotated by the cones and therefore inlet pressures are not needed to generate a rotating motion and thus the centrifugal separator is provided which can be gravity fed. Also the construction is such that no dead spots or areas of zero centrifugal force are present so that all particles in the separator are subjected to centrifugal force. Stated in another way, the apparatus develops within itself the centrifugal force necessary for efiicient dirt removal.

A unique feature of the apparatus is the consistency at which it operates. The apparatus effectively handles paper stock directly as it comes from a fiber pulper at about 2.5 to about 4% consistency and therefore thinning is not necessary in order to obtain proper operation. It is pointed out that such consistencies are satisfactory for refining, jordannin-g and for storage in chests and by providing fiber cleaning apparatus which effectively operates at these consistencies preparation equipment can be simplified and costs reduced.

Reverting nowto the annular chamber into which the rejected dirt particles are discharged, it is pointed out that the rejected particles settle downwardly into the venturi portion 40 and then finally settle into the collecting hopper F where they are allowed to accumulate for periodic removal. In order 'to accomplish this removal without interruption of service of the separator,

In Figure 2 a modification is illustrated to accomplish automatic discharge of the accumulated material from the collecting hopper F by means of automatically operating the inlet and discharge valves G and H. The valves are provided with operatingarms 47 and 48 interconnected by a link 49 and the upper arm 47 is connected to the piston rod 50 of an air cylinder and piston device 51, the cylinder of which is pivotally connected at 52 to a suitable support 53. The cylinder and piston device 51 is actuated to periodically empty the hopper F under control of a timer 54 of any well known form. In the position of Fig. 2 the timer has caused movement of the piston to its upper position in which the inlet valve G is open and the discharge valve H is closed. The timer may be set to cause movement of the piston to its lower position after a predetermined interval of time and this will cause the valve G to close and the valve H to open, thus discharging the accumulated particles from the hopper. Then after an interval the timer again operates to cause upward movement of the piston and so on.

The apparatus is capable of an exceedingly high output varying, of course, with the type of stock and the type of dirt to be removed. By way of example, in a standard board mill installation employing two cleaners constructed in accordance with the invention, each cleaner would effectively handle a total output of about seventyfive tons of exceptionally clean stock per day with a requirement of only about 13 H. P. per cleaner.

The small space requirementsrfor the apparatus and the simplicity of construction are important factors, a single shaft carrying the impeller cones and a direct connected motor comprising the moving parts of the apparatus.

A typical layout of a board machine stock preparation system includes a pulper to extract stock at consistencies which can be economically refined, jordanned and stored, a fiber cleaner following the pulper for removing abrasive dirt before the stock is fed to the refiners and jordans and then the refiners, jordans, consistency regulators and mix boxes. By employing a fiber cleaner or separator constructed in accordance with the present invention which operates. efliciently and effectively to clean stocks of consistencies of about 2.5% to about 4% whichare satisfactory for refining and jordanning, stock preparation equipment can be considerably simplified, with consequent reduction of equipment costs, maintenance costs and power requirements. Also operation at these consistencies reduces or entirely eliminates the need for the addition of thickeners before jordanning as would be required if the stock had to be thinned on introduction to the cleaning apparatus.

I claim:

1. Apparatus for separating foreign particles from paper stock, comprising a vertically disposed cylindrical casing, a vertically disposed shaft extending centrally through said casing, bearing means rotatively supporting said shaft, drive means for rotating said shaft, a plurality of truncated hollow cone members disposed concentric with said shaft, one above the other, and providing a flow passage for a column of stock from the top of said casing to the bottom thereof and a plurality of vertically spaced annular openings between adjacent cone members peripherally of said central flow passage, the wall of said casing being spaced fromsaid cone members to provide a chamber in surrounding relation thereto with which said plurality of annular openings communicate, impeller vane means secured to said shaft within said cones and exlet structure at the top of said casing for leading stock to said flow passage, and outlet structure at the bottom of said casing having an outlet for the discharge of cleaned stock from said stock flow passage and an outlet for the discharge of foreign particles from said surrounding chamber of the casing.

2. Apparatus according to claim 1 in which the cones and impeller vane means are connected for integral rotation.

3. Apparatus according to claim 1 in which said inlet structure includes an offset inlet portion, a discharge portion communicating with the flow passage provided by said cone members and a volute portion between said inlet and discharge portions.

4. Apparatus according to claim 1 in'which said outlet structure includes a venturi portion between the surrounding chambcr of the casing and the foreign particle discharge outlet.

5. Apparatus according to claim 1 inwhich said inlet structure is in the form of an elbow having an offset laterally disposed inlet portion, a downwardly directed outlet .portion communicating with the flow passage provided by the cone members, and a volute portion merging from said inlet portion to said outlet portion.

column of paper stock, comprising a vertically disposed cylindrical casing, rotating means disposed within said casing for defining a substantially continuous vertical passage and for positively rotating all particles in such a column, said means comprising a plurality of hollow truncated conical members concentric with said casing and disposed with the larger end of one such member adjacent the smaller end of the next said member, the outside diameter of the larger end of each such member being slightly smaller than the inside diameter of said casing, a central drive shaft extending through said conical members, and vane means within each conical member secured for rotation to said shaft and extending from said shaft to the inner surface of the associated conical member, inlet structure at the top of said casing for leading stock to said vertical passage, outlet structure at the bottom of said casing for conducting cleaned stock from said vertical passage, and an outlet for conducting foreign particles from the annular space between said casing and said conical members.

8. Apparatus for separating foreign particles from a column of paper stock, comprising a cylindrical casing, a rotor disposed within said casing and rotatable about the axis thereof, said rotor comprising a plurality of hollow truncated conical members disposed with the larger end of one member adjacent the smaller end of the next member, a central drive shaft extending through said conical members, and vane means interconnecting said shaft and said cone members, and defining, in cooperation with said cone members and said shaft, a continuous passage for a column of material extending through said rotor from end to end thereof, displaced radially from the rotor axis and insuring positive rotation of all parts of the column, the inner space of the casing and the outer surface of the rotor cooperating to form a generally annular space, the rotor having a plurality of discharge openings from said passage into said annular space, inlet structure for leading stock to one end of said passage, outlet structure for conducting cleaned stock from the other end of said passage, and outlet structure for conducting separated foreign particles from said annular space.

References Cited in the file of this patent UNITED STATES PATENTS 1,523,611 Ryding Jan. 20, 1925 2,174,857 Vogel-Jorgensen Oct. 3, 1939 2,542,095 Rouget Feb. 20, 1951 2,718,179 Cram Sept. 20, 1955 2,737,857 Lee Mar. 13, 1956 2,748,668 Hornbostel June 5, 1956 FOREIGN PATENTS 156,330 Australia May 4, 1954 

